1. Technical Field
The disclosure relates to an illumination assembly, in particular to an illumination assembly adapted to illuminate a display panel that is visible by reflecting environmental lights.
2. Related Art
Electro-Phoretic Display (EPD, also known as E-paper) has characteristics such as low power consumption and suitability for long term reading, and is therefore applied broadly to E-book apparatuses as the display panel installed therein.
EPD basically applies reflective-display technology, which displays a visible screen for a user mainly by reflecting environmental lights. However, under a low illumination environment, the screen displayed on such reflective type display panel is not readable for by user.
In order to resolve the problem under a low illumination environment, several traditional illumination solutions are proposed for liquid crystal displays. For example, U.S. Pat. No. 6,951,401 discloses a display illumination device, which includes two stacked light guides and a reflecting component for broadly distributing lights from a light source to a liquid crystal display panel; accordingly, the liquid crystals in the liquid crystal display panel may be illuminated by a backlight method. However, the design of two stacked light guides and a reflecting component in U.S. Pat. No. 6,951,401 obviously increase the thickness of the entire display module. U.S. Pat. No. 6,341,872 introduced another display illumination device, which includes a light guide and a light source. The light guide is stacked on the liquid crystal display panel. The light source is disposed at a side of the light guide for emitting lights from a lateral side, through the light guide and distributing lights to the liquid crystal display panel. In U.S. Pat. No. 6,341,872, the display module must reserve a certain border width to accommodate the light source and the light guide, which not only increases the border width, but also reduces the contrast ratio and reflectance of the liquid crystal display panel due to the light guide stacked thereon. In the prior art, the suitable illumination solutions mostly increase the border width or the thickness of the display module. More importantly, most of the traditional solutions are used to resolve the illumination problems on the liquid crystal display panel with backlight module. As for an EPD without a backlight module, relying on environmental light to illuminate the displayed screen, there is scarcely any suitable solution.